8223056: Remove Type-Stable-Memory support for Parkers

Reviewed-by: coleenp, rehn

src/hotspot/share/runtime/thread.cpp

@@ -1565,7 +1565,7 @@ JavaThread::JavaThread() :
   _should_post_on_exceptions_flag(JNI_FALSE),
   _thread_stat(new ThreadStatistics()),
 
-  _parker(Parker::Allocate(this)),
+  _parker(),
   _cached_monitor_info(nullptr),
 
   _class_to_be_initialized(nullptr),
@@ -1603,6 +1603,9 @@ JavaThread::JavaThread(bool is_attaching_via_jni) : JavaThread() {
 // interrupt support
 
 void JavaThread::interrupt() {
+  // All callers should have 'this' thread protected by a
+  // ThreadsListHandle so that it cannot terminate and deallocate
+  // itself.
   debug_only(check_for_dangling_thread_pointer(this);)
 
   // For Windows _interrupt_event
@@ -1700,10 +1703,6 @@ JavaThread::~JavaThread() {
   // Ask ServiceThread to release the threadObj OopHandle
   ServiceThread::add_oop_handle_release(_threadObj);
 
-  // JSR166 -- return the parker to the free list
-  Parker::Release(_parker);
-  _parker = NULL;
-
   // Return the sleep event to the free list
   ParkEvent::Release(_SleepEvent);
   _SleepEvent = NULL;